DE102009036391A1 - Process for producing an olefin polymer (1) - Google Patents

Abstract

The object of the present invention is to provide a process for producing an olefin polymer, whereby an olefin polymer having a higher molecular weight can be produced by efficiently reducing the hydrogen concentration in the polymerization of an olefin in the presence of hydrogen using a gas phase reaction vessel. Described is a process for producing an olefin polymer comprising the steps of using a gas phase reaction vessel, polymerizing an olefin using an olefin polymerization catalyst in the presence of hydrogen, and adding a hydrogenation catalyst to a bed region in the gas phase reaction vessel.

Description

Field of the invention

The The present invention relates to a process for producing a Olefin polymer.

Background of the invention

So far is under in a process for producing an olefin polymer Use of a gas phase polymerization reaction in the presence of Hydrogen a method of controlling the hydrogen concentration within a gas phase polymerization reaction vessel known to reduce the hydrogen concentration within of the gas phase polymerization reaction vessel Removing a portion of a hydrogen-containing gas in the gas phase polymerization reaction vessel, then adding hydrogen in the withdrawn Gas to an olefin for hydrotreating the gas and then again Feeding the hydrotreated gas into the polymerization reaction vessel. (See, for example, Patent Document 1)

• Patentdokument 1: JP-A-10-204123
• Patentdokument 2: JP-A-8-151408

Further, in a process for producing an olefin polymer in the presence of hydrogen, a method for controlling the molecular weight distribution or the like of the produced olefin polymer by adding a hydrogenation catalyst to a reaction vessel for reducing the hydrogen concentration is known. (See, for example, Patent Document 2)

• Patent Document 1: JP-A-10-204123
• Patent Document 2: JP-A-8-151408

Brief summary of the invention

however it was in the method for controlling the hydrogen concentration, which is disclosed in the above Patent Document 1, necessary separately to provide a reaction layer to a hydrogenation catalyst to use, and there was a problem that clogging the Reaction layer or a conduit of circulating gas or causes an impairment of the catalyst performance has been.

Further when a hydrogenation catalyst for gas phase polymerization according to the disclosure in the above patent document 2 was used, the problem that the hydrogen concentration depending on the location in a gas phase reaction vessel, where the hydrogenation catalyst was added is insufficient could be reduced.

in the In view of this present situation lies the task of the present invention in providing a method for producing an olefin polymer, whereby an olefin polymer with a higher molecular weight through efficient reduction the concentration of hydrogen in the polymerization of an olefin in the presence of hydrogen using a gas phase reaction vessel can be produced.

at a process for producing an olefin polymer which is the use a gas phase reaction vessel and the polymerization an olefin using an olefin polymerization catalyst in the presence of hydrogen, the inventors devoted themselves the present invention of investigating the location in the gas phase reaction vessel, to which a hydrogenation catalyst should be added. They determined as a result, that by the addition of a hydrogenation catalyst to a bed area in the gas phase reaction vessel Efficiently reduced hydrogen concentration and an olefin polymer with a higher molecular weight even in the presence of hydrogen can be prepared, and they arrived at the present Invention.

The present invention therefore relates to a process for the preparation of an olefin polymer which comprises the following steps:
Use of a gas phase reaction vessel, polymerization of an olefin using a catalyst for olefin polymerization in the presence of hydrogen and
Adding a hydrogenation catalyst to a bed region in the gas phase reaction vessel.

Advantages of the invention

By the process for producing an olefin polymer according to the The present invention can provide an olefin polymer having a higher Molecular weight can also be produced in the presence of hydrogen.

in the The following will explain the present invention in more detail.

The Process for the preparation of an olefin polymer according to present invention is characterized in that it is the stage the addition of a hydrogenation catalyst to a bed region in a gas phase reaction vessel in a process for the preparation of an olefin polymer, which involves the use of the gas phase reaction vessel and the polymerization of an olefin using a catalyst for olefin polymerization in the presence of hydrogen.

The bed region to which the hydrogenation catalyst used in the present invention is added is a powder concentrated region having a bulk density of polymerized powder of not less than 0.10 g / cm ³ in a gas phase reaction vessel. In the present invention, a hydrogenation catalyst is preferably added to a bed region having a bulk density of polymerized powder of not less than 0.13 g / cm ³ and not more than 0.70 g / cm ^3, and more preferably a hydrogenation catalyst a bed region having a bulk density of polymerized powder of not less than 0.16 g / cm ³ and not more than 0.50 g / cm ^{3 was} added.

hydrogenation

Of the Hydrogenation catalyst used in the present invention is a catalyst with the ability to selectively hydrogenate of olefinic unsaturated double bonds, and hydrogen, the is present in a gas phase reaction vessel, reacts with an olefin such. As propylene, ethylene or the like. and is removed as propane or ethane. As hydrogenation catalyst publicly known hydrogenation catalysts are cited. For example, compounds that include titanium, platinum, palladium, Palladium-chromium, nickel or ruthenium, and specifically (a) the above metals, (b) oxides of the above metals, (c) halides the above metals, (d) compounds wherein the above (a), (b), (c) or the like on a porous support such as silica or alumina, and the like.

The Nickel-containing compound includes, for example, bis (1,5-cyclooctadiene) nickel, Bis (cyclopentadienyl) nickel, tetrakis (diethylphenylphosphonite) nickel, Tetrakis (methyldiphenylphosphine) nickel, tetrakis (trifluorophosphine) nickel and the like.

The titanium-containing compound includes titanocene compounds having, as a ligand, at least one kind selected from the group consisting of a cyclopentadienyl group, an indenyl group, a fluorenyl group and their derivatives, and non-titanocene compounds having as a ligand at least one kind derived from the A group of a dialkylamino group, an alkoxy group, a phenoxy group, an aryloxy group, a thioalkoxy group, a thioaryloxy group, an alkylamino group, an arylamino group, an alkylphosphino group, an arylphosphino group, a group represented by the following general formula [1], a group shown below general formula [2] and derivatives thereof. R ¹ ₃ P = N- [1]

In the formula, R ^{1 represents} a hydrogen atom, a halogen atom, a hydrocarbon group, a halogenated hydrocarbon group, a hydrocarbonoxy group, a silyl group or an amino group, wherein the three R ^{1 's may be the} same or different and two or more of them may be bonded to each other can or can form a ring.

In the formula, R ^{2 represents} a hydrogen atom, a halogen atom or a hydrocarbon group, wherein the plural R ^{2 's may be the} same or different and two or more of them may be bonded together or form a ring.

Compounds wherein the above (a), (b), (c) or the like are supported on a porous support such as silica or alumina include, for example, Pd / Al ₂ O ₃ , Pd / SiO ₂ .Al ₂ O ₃ , Pd SiO ₂ , Pt / Al ₂ O ₃ and the like

Of these, a titanocene compound is preferred. As the titanocene compound, for example
Bis (cyclopentadienyl) titanium,
Bis (cyclopentadienyl) titandibromid,
Bis (cyclopentadienyl) titandiiodid,
Bis (cyclopentadienyl) titanium difluoride,
Bis (cyclopentadienyl) titanchlorbromid
Bis (cyclopentadienyl) titanmethoxychlorid,
Bis (cyclopentadienyl) titanethoxychlorid,
Bis (cyclopentadienyl) titanphenoxychlorid,
Bis (cyclopentadienyl) titanium dimethoxide and the like.

Further are as the hydrogenation catalysts used in the present invention those which are liquid or in a state in which they are preferred which they are soluble in a solvent present.

In addition, the hydrogenation catalyst used in the present invention may be used in combination with a reducing agent. As the reducing agent, there may be mentioned, for example, an organic aluminum compound, an organic lithium compound, an organic magnesium compound, an organic zinc compound and the like. Of these is a use in combination with an organic aluminum miniumverbindung preferred.

The The above organic aluminum compound includes, for example Trialkylaluminum, an alkylaluminum halide, an alkylaluminum hydride Aluminum alkoxide, an aluminoxane and the like.

One Trialkylaluminum includes, for example, trimethylaluminum, triethylaluminum, Triisobutylaluminum, trihexylaluminum, trioctylaluminum, tridecylaluminum and the like.

One Alkylaluminum halide includes, for example, diethylaluminum monochloride, Diisobutylaluminum monochloride, ethylaluminum sesquichloride, ethylaluminum dichloride and the like.

One Alkylaluminum hydride includes, for example, diethylaluminum hydride, Diisobutylaluminum hydride and the like.

One Aluminum alkoxide includes, for example, diethyl aluminum oxide, Diethylaluminum phenoxide and the like.

One Aluminoxane includes, for example, methylaluminoxane, ethylaluminoxane, Isobutylaluminoxane, methylisobutylaluminoxane and the like.

From these are a trialkylaluminum and a triethylaluminum even more preferred.

she can be singly or in a combination of two or more species are used.

The Molar ratio of a reducing agent and a metal atom in a hydrogenation catalyst is preferably 1: 1 to 30: 1, more preferably 2: 1 to 10: 1 and even stronger preferably 3: 1 to 7: 1.

One Hydrogenation catalyst can after dilution with a inert organic solvents are supplied. Here, the hydrogenation catalyst may be previously with a reducing agent be brought into contact. The above inert organic solvent means a solvent that works with everyone in the hydrogenation reaction not responding to participating materials. As a preferred solvent are aliphatic hydrocarbons, such as butane, pentane, hexane, Heptane, octane and the like, and the isomers thereof and cycloaliphatic Hydrocarbons such as cyclohexane, cycloheptane and the like, and the Derivatives thereof.

Of the Hydrogenation catalyst used in the present invention is preferably a material containing a titanocene compound, more preferably a compound obtained by contacting a titanocene compound and a reducing agent is formed, and even more preferably, a compound that is contacted by contacting a titanocene compound and an organic aluminum compound is formed.

Catalyst for olefin polymerization

As the catalyst for olefin polymerization used in the present invention, publicly known polymerization catalysts used for olefin polymerization can be used, and Ziegler-Natta catalysts described in, for example, US Pat JP-A-57-63310 . JP-A-58-83006 . JP-A-61-78803 . JP-A-7-216017 . JP-A-10-212319 . JP-A-62-158704 and JP-A-11-92518 or metallocene-type catalysts disclosed in U.S. Pat JP-A-5-155930 . JP-A-9-143217 . JP-A-2002-293817 . JP-A-2003-171412 . JP-A-8-511044 and JP-A-2001-31720 are disclosed.

• Komponente (a): eine feste Komponente, die Titan, Magnesium und ein Halogen enthält,
• Komponente (b): eine organische Aluminiumverbindung und
• Komponente (c): eine Elektronendonorverbindung.

Ziegler-Natta catalysts are preferably materials formed by contacting the below-mentioned component (a) and the following component (b), and even more preferably materials prepared by contacting the following component (a), the following component (b) and the component (c) indicated below are formed:

• Component (a): a solid component containing titanium, magnesium and a halogen,
• Component (b): an organic aluminum compound and
• Component (c): an electron donor compound.

• (1) ein Verfahren des Inkontaktbringens von einer halogenierten Magnesiumverbindung und einer Titanverbindung,
• (2) ein Verfahren des Inkontaktbringens von einer halogenierten Magnesiumverbindung, einem Elektronendonor und einer Titanverbindung,
• (3) ein Verfahren des Lösens von einer halogenierten Magnesiumverbindung und einer Titanverbindung in einem Elektronendonor-Lösemittel unter Bildung einer Lösung und des anschließenden Tränkens eines Trägermaterials mit der Lösung,
• (4) ein Verfahren des Inkontaktbringens von einer Dialkoxymagnesiumverbindung, einer halogenierten Titanverbindung und einem Elektronendonor und
• (5) ein Verfahren des Inkontaktbringens von einer festen Komponente, die Magnesiumatome, Titanatome und Kohlenwasserstoffoxygruppen enthält, einer halogenierten Verbindung und einem Elektronendonor und/oder einem Halogenid einer organischen Säure.

As examples of a method for producing the solid component (a) containing titanium, magnesium and a halogen, the following methods (1) to (5) can be given.

• (1) a method of contacting a halogenated magnesium compound and a titanium compound,
• (2) a method of contacting a halogenated magnesium compound, an electron donor and a titanium compound,
• (3) a method of dissolving a halogenated magnesium compound and a titanium compound in an electron donor solvent to form a solution and then soaking a carrier material with the solution,
• (4) a method of contacting a dialkoxymagnesium compound, a halogenated titanium compound and an electron donor, and
• (5) a method of contacting a solid component corresponding to magnesium atoms, titanium atoms and hydrocarbonoxy groups a halogenated compound and an electron donor and / or a halide of an organic acid.

From this is the solid component obtained by the method (5) and a solid component containing a phthalic acid ester compound as Contains electron donor, more preferred.

A Organic aluminum compound of component (b) includes, for example a trialkylaluminum, an alkylaluminum halide, an alkylaluminum hydride, an aluminum alkoxide, an aluminoxane and the like.

One Trialkylaluminum includes, for example, trimethylaluminum, triethylaluminum, Triisobutylaluminum, trihexylaluminum, trioctylaluminum, tridecylaluminum and the like.

One Alkylaluminum halide includes, for example, diethylaluminum monochloride, Diisobutylaluminum monochloride, ethylaluminum sesquichloride, ethylaluminum dichloride and the like.

One Alkylaluminum hydride includes, for example, diethylaluminum hydride, Diisobutylaluminum hydride and the like.

One Aluminum alkoxide includes, for example, diethylaluminum ethoxide, Diethylaluminum phenoxide and the like.

One Aluminoxane includes, for example, methylaluminoxane, ethylaluminoxane, Isobutylaluminoxane, methylisobutylaluminoxane and the like.

From these are a trialkylaluminum and triethylaluminum more preferred.

she can be singly or in a combination of two or more species are used.

As the electron donor compound of the component (c), a silicon compound represented by the following general formula [3] is preferably used: R ³ _r Si (OR ⁴ ) _4-r [3] wherein R ^{3 is} a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms or a heteroatom-containing group, R ^{4 is} a hydrocarbon group having 1 to 20 carbon atoms and r is an integer of 0 to 3 and when more radicals R ³ are present, a plurality of radicals R ^{3 may be} the same or different, and when more radicals R ⁴ are present, a plurality of radicals R ^{4 may be} the same or different.

A hydrocarbon group having 1 to 20 carbon atoms for R ³ includes, for example, a straight-chain alkyl group having 1 to 20 carbon atoms, a branched-chain alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 1 to 20 carbon atoms, a cycloalkenyl group having 1 to 20 carbon atoms, an aryl group having 1 to 20 carbon atoms and the like.

A straight-chain alkyl group having 1 to 20 carbon atoms for example, a methyl group, an ethyl group, a propyl group, a Butyl group, a pentyl group and the like.

A branched-chain alkyl group having 1 to 20 carbon atoms for example, an isopropyl group, a sec-butyl group, a tert-butyl group, a tert-amyl group and the like.

A Cycloalkyl group having 1 to 20 carbon atoms includes, for example a cyclopentyl group, a cyclohexyl group and the like.

A Cycloalkenyl group of 1 to 20 carbon atoms includes, for example a cyclopentenyl group and the like.

A For example, an aryl group having 1 to 20 carbon atoms includes a phenyl group, a tolyl group and the like.

A heteroatom-containing group for R ³ includes, for example, an oxygen atom-containing group, a nitrogen atom-containing group, a sulfur atom-containing group, a phosphorus atom-containing group and the like. In particular, a dialkylamino group such as. A dimethylamino group, a methylethylamino group, a diethylamino group, an ethyl-n-propylamino group or a di-n-propylamino group, a pyrrolyl group, a pyridyl group, a pyrrolidinyl group, a piperidyl group, a perhydroindolyl group, a perhydroisoindolyl group, a perhydroquinolyl group, a perhydroisoquinolyl group, a Perhydrocarbazolyl group, a perhydroacridinyl group, a furyl group, a pyranyl group, a perhydrofuryl group, a thienyl group and the like. Among them, a group having a hetero atom capable of directly bonding to the silicon atom of a silicon compound is preferable.

A hydrocarbon group having 1 to 20 carbon atoms for R ⁴ includes those which are the same as those exemplified as a hydrocarbon group having 1 to 20 carbon atoms for R ³ .

A preferred electron donor compound of component (c) is a silicon compound having as R ³ at least one hydrocarbon group having a secondary or tertiary carbon atom, which is bonded directly to a silicon atom, or at least one dialkylamino group in the above-mentioned general formula [3].

preferred concrete examples of an electron donor compound of Component (c) include diisopropyldimethoxysilane, di-tert-butyldimethoxysilane, tert-butylmethyldimethoxysilane, tert-butylethyldimethoxysilane, tert-butyl-n-propyldimethoxysilane, tert-butyl-n-butyldimethoxysilane, tert-amylmethyldimethoxysilane, tert-amylethyldimethoxysilane, tert-amyl-n-propyldimethoxysilane, tert-amyl-n-butyldimethoxysilane, isobutylisopropyldimethoxysilane, tert-butylisopropyldimethoxysilane, Dicyclobutyldimethoxysilane, cyclobutylisopropyldimethoxysilane, cyclobutylisobutyldimethoxysilane, Cyclobutyl-tert-butyldimethoxysilane, dicyclopentyldimethoxysilane, Cyclopentylisopropyldimethoxysilane, cyclopentylisobutyldimethoxysilane, Cyclopentyl-tert-butyldimethoxysilane, dicyclohexyldimethoxysilane, Cyclohexylmethyldimethoxysilane, cyclohexylethyldimethoxysilane, cyclohexylisopropyldimethoxysilane, Cyclohexylisobutyldimethoxysilane, cyclohexyl-tert-butyldimethoxysilane, cyclohexylcyclopentyldimethoxysilane, Cyclohexylphenyldimethoxysilane, diphenyldimethoxysilane, phenylmethyldimethoxysilane, Phenylisopropyldimethoxysilane, phenylisobutyldimethoxysilane, phenyl-tert-butyldimethoxysilane, Phenylcyclopentyldimethoxysilane, diisopropyldiethoxysilane, diisobutyldiethoxysilane, Di-tert-butyldiethoxysilane, tert-butylmethyldiethoxysilane, tert-butylethyldiethoxysilane, tert-butyl-n-propyldiethoxysilane, tert-butyl-n-butyldiethoxysilane, tert-amylmethyldiethoxysilane, tert-amylethyldiethoxysilane, tert-amyl-n-propyldiethoxysilane, tert-amyl-n-butyldiethoxysilane, Dicyclopentyldiethoxysilane, dicyclohexyldiethoxysilane, cyclohexylmethyldiethoxysilane, Cyclohexylethyldiethoxysilane, diphenyldiethoxysilane, phenylmethyldiethoxysilane, 2-norbornanemethyldimethoxysilane, bis (perhydroquinolino) dimethoxysilane, Bis (perhydroisoquinolino) dimethoxysilane, (perhydroquinolino) (perhydroisoquinolino) dimethoxysilane, (Perhydroquinolino) methyldimethoxysilane, (perhydroisoquinolino) methyldimethoxysilane, (Perhydroquinolino) ethyldimethoxysilane, (perhydroisoquinolino) ethyldimethoxysilane, (Perhydroquinolino) (n-propyl) dimethoxysilane, (perhydroisoquinolino) (n-propyl) dimethoxysilane, (perhydroquinolino) (tert-butyl) dimethoxysilane, (Perhydroisoquinolino) (tert-butyl) dimethoxysilane and diethylaminotriethoxysilane.

she can be singly or in a combination of two or more species are used.

When a metallocene-type catalyst is used as a catalyst for olefin polymerization, as the metallocene compound, a metallocene compound represented by the following general formula [4] is preferable: Cp _n MX _4-n [4] wherein Cp is a group selected from a substituted or unsubstituted cyclopentadienyl group, indenyl group or fluorenyl group, M is an element selected from zirconium and hafnium, X is a group consisting of hydrogen, a halogen, an alkoxy group is an amino group, an alkyl group having 1 to 10 carbons or an aryloxy group, a plurality of Cp and X may be bonded to each other through a linking group, and n is an integer of 1 to 3.

polymerisation

The Process for the preparation of an olefin polymer according to present invention can not only for a discontinuous Polymerization process but also a continuous polymerization process be used. Further, if, for example, a catalyst metallocene-type catalyst used as olefin polymerization catalyst is, in many cases, the formed olefin polymers the ends of which have unsaturated bonds. Apparently Such unsaturated bonds by dehydrogenation of the initially formed saturated ends and therefore there is a possibility that such hydrogen is gradually concentrated in a circulating olefin. Therefore, in such a case, the present invention may be considered Technology for controlling the concentration of hydrogen in a single Polymerization be used.

Further In some cases, the present invention is also included a multi-stage polymerization with several polymerization stages necessary with different polymerization conditions. at In a multistage polymerization, the polymerization may be by change the polymerization conditions carried out in a single reaction vessel or the polymerization in several reaction vessels with different polymerization conditions, these being in Are connected in series. The present invention can, if the hydrogen concentration in the subsequent stage is efficiently reduced compared to the previous stage, be used in a single reaction vessel or to hydrogen, with powder from the reaction vessel of previous stage in the reaction vessel of the following Stage flows, reducing efficiently, in a multi-level Polymerization using several reaction vessels be used.

Therefore, in the process for producing an olefin polymer according to the present invention, if an olefin is polymerized in the presence of a hydrogen-containing gas phase that is, one-stage polymerization using singular polymerization conditions may be performed, or multi-stage polymerization consisting of plural polymerization stages having different polymerization conditions may be performed, and polymerization may be carried out using a single reaction vessel or polymerization may be carried out using a plurality of reaction vessels. Here, polymerization conditions means the polymerization form, temperature, pressure, raw material composition and the like, and the polymerization form means liquid phase polymerization or gas phase polymerization. When a multi-stage polymerization is used, liquid-phase polymerization or gas-phase polymerization may be carried out at a stage prior to the polymerization step in which a hydrogenation catalyst is added. Liquid phase polymerization means bulk polymerization or slurry polymerization, and gas phase polymerization means a mixed vessel type gas phase polymerization, a fluidized bed type gas phase polymerization or a riser bed type gas phase polymerization. As the gas phase polymerization, in the present invention, a fluidized bed type is preferable, with a gas flowing vertically and upwardly in a cylindrical reaction vessel equipped with a gas distribution plate.

Of the Addition site of a hydrogenation catalyst in a gas phase polymerization of the fluidized bed type is sufficient for mixing a polymer and a hydrogenation catalyst and increasing the hydrogenation power preferably within a bed area, formed immediately above a distributor plate is. When the height of a distributor plate is assumed to be 0 and the height of a bed area is assumed to be H, a hydrogenation catalyst is preferably a range with a Level of 0 to 0.5 H added and more preferred an area with a height of 0 to 0.3 H added.

in the With regard to the amount of hydrogenation catalyst introduced is the molar amount of a metal atom in a hydrogenation catalyst to 1 kg of polymerized powder in a reaction vessel (mmol / kg) preferably not less than 0.0001 mmol / kg and not more than 1 mmol / kg, more preferably not less than 0.0003 mmol / kg and not more than 0.5 mmol / kg, and more preferably not less than 0.001 mmol / kg and not more than 0.1 mmol / kg.

Further For example, a hydrogenation catalyst may be continuous or intermittent be entered in a reaction vessel.

Main Polymerization

at the process for producing an olefin polymer according to the The present invention can be prepared in a gas-phase reaction vessel Olefin polymer be a homopolymer or a copolymer. As examples for a polymerizable in the present invention Olefin can be ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 4-methyl-1-pentene, 3-methyl-1-pentene, styrene, Butadiene, isoprene, 1,4-hexadiene, dicyclopentadiene, 5-ethylidene-2-norbornene and the like, and the olefin becomes dependent determined by the nature of the desired polymer product. The If, for example, polyethylene, polypropylene, polybutene and the like, as a homopolymer product, and EPR (ethylene-propylene copolymer), PBR (Propylene-butene copolymer), EPBR (ethylene-propylene-butene copolymer) and the like are prepared as a copolymer product are in the polymerization to be used olefins ethylene, propylene and butene and in some Cases become an extremely small amount the other olefins used.

in the In the case of multi-stage polymerization, the same polymer may be used can be made in any stage or it can be polymers of different compositions. For the case where the same polymer is produced at each stage, For example, the hydrogen content in the gas phase reactor may be the following Stage by adding a hydrogenation catalyst to a bed area be reduced in the gas phase reactor of the subsequent stage and therefore an olefin polymer having a broader molecular weight distribution, wherein a polymer prepared in the subsequent step is a higher Molecular weight than that of one produced in the previous stage Polymer produced. Furthermore, for the case that polymers of different compositions in each Stage, the present invention in the preparation an olefin polymer used, the one in the preceding Stage produced lower molecular weight polymer and a polymer prepared in the subsequent step which comprises has higher molecular weight and one opposite which has a different composition from the previous stage, contains.

The process for producing an olefin polymer according to the present invention is preferably a process for producing an ethylene-propylene block copolymer, said process comprising a first polymerization step of polymerizing propylene in the presence of hydrogen and an olefin polymerization catalyst to form a propylene homopolymer and a second polymerization step the polymerization of ethylene and propylene in the presence of the propylene homopolymer obtained in the first polymerization step to form an ethylene-propylene copolymer, the second polymerization step further comprising the steps of using a gas phase reaction vessel and adding a hydrogenation catalyst to a bed region in the gas phase reaction vessel.

at the above process for producing an ethylene-propylene block copolymer is the ratio of intrinsic viscosity of the propylene homopolymer obtained in the first polymerization stage Intrinsic viscosity of the second stage of polymerization obtained ethylene-propylene copolymer preferably 2 to 20, more preferably 2.5 to 15 and even more preferably 3.5 to 10th

The first polymerization and / or the second polymerization can be a one-step polymerization or multi-step Polymerization be.

The Polymerization temperature is dependent on the type a monomer, the molecular weight of a product and the like. Different, However, it is not more than the melting point of a Olefinpolymer, preferably it is around 10 ° C. or more less than the melting point, more preferable from room temperature to 200 ° C, more preferably 40 to 160 ° C, and most preferably 60 to 130 ° C. Further, the polymerization temperature is within this range to hold the polymerization system through a cooling device cooled. Further, the polymerization pressure is more atmospheric Pressure to 15 MPa, preferably 0.2 to 7 MPa and more preferably 1 to 5 MPa.

If the present invention for a multi-stage polymerization is used, the hydrogen concentration of a gas phase region in the previous stage under the condition of not more than 30% held. Even if the hydrogen concentration of a Altitude exceeding 30% is not special Problem with the execution of the manufacturing process according to the present invention, but increased a large amount of hydrogen in the subsequent stage introducing the concentration of the olefin hydride (propane, Ethane or the like) prepared in a gas phase reaction vessel and reduces the polymerization activity in the subsequent stage, and it is therefore not favorable if the hydrogen concentration is too high.

Further it is when a hydrogenation catalyst is added in a gas phase reaction vessel, favorable, with a view to improving powder properties and an improvement in polymer properties is a step of addition a polymerization activity lowering agent in to provide a polymerization reaction system.

The used herein, lowering the polymerization activity Means includes, for example, an electron donor compound, a active hydrogen-containing compound and an oxygen-containing one Compound at normal temperatures and normal pressures is gaseous, and the lowering means generally has the Effect of reducing the activity of an olefin polymerization catalyst on.

The Electron donating compound includes alkoxysilanes, esters, ethers and like.

The active hydrogen-containing compound includes alcohols, water and the like.

The Oxygen-containing compound at normal temperatures and normal pressures is gaseous, includes oxygen, Carbon monoxide, carbon dioxide and the like.

The Alkoxysilanes include tetrabutoxysilane, tetraethoxysilane, tetramethoxysilane and the like.

The Alcohols include methanol, ethanol, propanol, butanol and the like.

The the polymerization activity lowering agent is preferable an active hydrogen-containing compound or an oxygen containing compound at normal temperatures and normal Pressing is gaseous, more preferably one Alcohol, oxygen or carbon monoxide and even stronger preferably methanol, ethanol, propanol, butanol, oxygen or Carbon monoxide.

The the polymerization activity lowering agents can used singly or in a combination of two or more species become.

prepolymerization

Before the polymerization step, a small amount of an olefin may be polymerized (hereinafter referred to as prepolymerization) to form a prepolymerization catalyst component. As examples of an olefin which may be prepolymerized there may be mentioned ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 4-methyl-1-pentene, 3-methyl-1. pentene, styrene, butadiene, isoprene, 1,4-hexadiene, dicyclopentadiene, 5-ethylidene-2-norbornene and the like. The amount of an olefin to be prepolymerized is usually 0.1 to 200 g per g of the catalyst component. As a method for prepolymerization publicly known Verfah as a method of feeding a small amount of an olefin in the presence of the catalyst component and an organic aluminum compound and performing a pre-polymerization in a slurry state using a solvent. As the solvent used in the prepolymerization, inert hydrocarbons such as propane, butane, isobutane, pentane, isopentane, hexane, heptane, octane, cyclohexane, benzene, toluene and the like, and liquid olefins are mentioned, and they may be in a mixture of two or more Species can be used. Further, the slurry concentration in the prepolymerization is usually 1 to 500 g, and preferably 3 to 150 g by weight of the catalyst component contained in 1 l of a solvent.

The Amount of an organic aluminum compound used in prepolymerization is used is 0.1 to 700 moles per mole of transition metal atoms, which are contained in the catalyst component, preferably 0.2 to 200 mol, and more preferably 0.2 to 100 mol. at The prepolymerization may, if necessary, an electron donor such as Alkoxysilicon compound or the like. The amount of one used electron donor is preferably 0.01 to 400 moles per mole of transition metal atoms present in the catalyst component more preferably 0.02 to 200 mol, even more preferably 0.03 to 100 mol.

The Prepolymerization temperature is usually -20 to + 100 ° C, and preferably 0 to + 80 ° C. Further the prepolymerization time is usually 2 min to 15 h.

Examples

in the The following will illustrate the present invention by way of examples and comparative examples explained. The measurements and judgments of physical Properties were according to the procedures given below carried out.

(1) intrinsic viscosity (unit: dl / g)

Using an Ubbelohde viscometer, relative viscosities were determined at the three concentrations of 0.1, 0.2 and 0.5 g / dl under the conditions of the solvent tetralin and the temperature of 135 ° C. Then, the intrinsic viscosity was measured by an extrapolation method of plotting the relative viscosities against the concentrations and extrapolating the concentrations to 0 according to the calculation method as disclosed in US Pat "Polymer Solution, Polymer Experimental Study 11" (published by Kyoritsu Shuppan Co., Ltd., 1982), page 491 , receive.

(2) Content of copolymerized part (unit: wt%)

Pa:

Polymergewicht pro h, das aus dem dritten Schritt der Propylenpolymerisationsstufe ausgetragen wurde

Pb:

Polymergewicht pro h, das aus dem ersten Schritt der Copolymerisationsstufe ausgetragen wurde

The copolymerized part X content (% by weight) prepared in the first step of the copolymerization step was calculated by the following formula. X = (Pb-Pa) / Pb × 100

Pa:

Polymer weight per hr discharged from the third step of the propylene polymerization step

Pb:

Polymer weight per hr discharged from the first step of the copolymerization step

(3) intrinsic viscosity (unit: dl / g) of the polymer produced in the copolymerized part

[η]1:

Grenzviskosität (dl/g) des Polymers nach dem dritten Schritt der Propylenpolymerisationsstufe

[η]2:

Grenzviskosität (dl/g) des Polymers nach dem ersten Schritt der Copolymerisationsstufe

The intrinsic viscosity [η] a (dl / g) of the polymer component prepared in the third step of the propylene polymerization step and intrinsic viscosity [η] b (dl / g) of the polymer component prepared in the first step of the copolymerization step were calculated by the formulas given below. [η] a = [η] 1 [η] b = ([η] 2 - [η] a × (1-X / 100)) / (X / 100)

[Η] 1:

Intrinsic viscosity (dl / g) of the polymer after the third step of the propylene polymerization step

[Η] 2:

Intrinsic viscosity (dl / g) of the polymer after the first step of the copolymerization step

example 1

Preparation of a solution titanocene

The Inside a flask with an internal volume of 1 l was through Replaced nitrogen. Into this vessel were 4.5 g dicyclopentadienyltitanium dichloride (manufactured by KANTO CHEMICAL CO., INC.) And 928 ml of hexane and simultaneously at room temperature stirred and 72 mmol of triethylaluminum were added, whereby a solution was obtained. This solution was further diluted with hexane.

prepolymerization

Into an autoclave made of SUS having an inner volume of 3 liters and a fitted stirrer, 1.5 liters of n-hexane sufficiently subjected to dehydration and degassing treatment, 30 mmol of triethylaluminum and 3.0 mmol of cyclohexylethyldi methoxysilane registered. To this was added 16 g of a solid catalyst component prepared by the method of Example 1 of Japanese Patent Application 2008-27945 32 g of propylene was continuously fed in about 40 minutes while the temperature in the autoclave was maintained at about 3 to 10 ° C, and prepolymerization was conducted. Subsequently, the prepolymerized slurry was transferred to an autoclave made of SUS having an inner volume of 200 L and a fitted stirrer, and 132 L of liquid butane was added to form a prepolymerization catalyst component slurry.

Under Use of the prepolymerization catalyst component slurry prepared as described above were three steps of propylene homopolymerizations respectively in various reactors for the production of polypropylene particles. Subsequently, in the presence of the polypropylene particles a one-step copolymerization of propylene and ethylene for the preparation of a propylene-ethylene block copolymer. Hereinafter each polymerization step is explained.

First step of propylene polymerization (Liquid Phase)

Using a Bessel type reactor having an inner volume of 163 L and a fitted stirrer, homopolymerization of propylene was carried out. That is, propylene, hydrogen, triethylaluminum, cyclohexylethyldimethoxysilane, and the prepolymerization catalyst component slurry were continuously fed to the reactor. The reaction conditions were a polymerization temperature of 73 ° C, a stirring speed of 150 ^rpm-1, a quantity of liquid of the reactor of 44 l, a feed rate of propylene of 25 kg / h, a feed rate of hydrogen of 160 Nl / h, a feed rate of triethylaluminum of 40.6 mmol / hr, a feed rate of cyclohexylethyldimethoxysilane of 5.9 mmol / hr and a feed rate of the prepolymerization catalyst component slurry (calculated in terms of the polymerization catalyst component) of 0.445 g / hr. In the reactor, the average residence time of the slurry was 0.73 hours and the amount of discharged polypropylene particles was 5.0 kg / h.

Second step of the propylene polymerization (Liquid Phase)

The slurry which had undergone the above first propylene polymerization was continuously transferred to another reactor (Bessel type), and the homopolymerization of propylene was further carried out. In this connection, no supply of propylene and hydrogen to the reactor. The reaction conditions were a polymerization temperature of 69 ° C, a stirring speed of 150 rpm ^-1, and a quantity of liquid of the reactor of 44 l. In the reactor, the average residence time of the slurry was 0.84 hours and the amount of discharged polypropylene particles was 9.3 kg / h.

Third step of propylene polymerization (Gas phase polymerization)

The polypropylene particles obtained by the above second propylene polymerization were continuously transferred to a fluidized bed reactor having an internal volume of 1.4 m ³ and a fitted stirrer, propylene and hydrogen were continuously supplied to this reactor, and homopolymerization of propylene was further carried out while discharging excess gas was to keep the pressure constant. The reaction conditions were a polymerization temperature of 80 ° C, a polymerization pressure of 1.8 MPa, a flow rate of the circulating gas of 100 m ³ / h, a feed rate of propylene of 10 kg / h, a feed rate of hydrogen of 930 Nl / h and a polymer particle holding amount in the fluidized bed of 50 kg. In the reactor, the average residence time of polymer particles was 3.5 hours, the gas concentration ratio (mol%) of hydrogen / (hydrogen + propylene) in the reactor was 8.9, the amount of discharged polymer particles was 14.1 kg / hr, and the intrinsic viscosity the same 0.97 dl / g.

First step of copolymerization (gas phase polymerization reaction)

The polypropylene particles obtained by the above third propylene polymerization were continuously transferred to another fluidized bed reactor having an internal volume of 1 m ³ and equipped with a gas diffusion plate and a stirrer; Propylene, ethylene and hydrogen were continuously supplied to this reactor, and copolymerization of propylene and ethylene was conducted while the excess gas was discharged to keep the pressure constant. The reaction conditions were a polymerization temperature of 70 ° C, a polymerization pressure of 1.4 MPa, a flow rate of the circulating gas of 150 m ³ / h, a feed rate of propylene of 22.5 kg / hr, a feed rate of ethylene of 8.3 kg / h, a feed rate of hydrogen of 200 Nl / h and a polymer particle holding amount in the fluidized bed of 55 kg. Further, to the bed portion, the above-mentioned solution of a titanocene compound was added in an amount corresponding to 2.56 mmol as calculated in terms of the molecular weight of titanocene, per mole of triethylaluminum nium, which was supplied to the reactor of the first step of the propylene polymerization, given. The bulk density of the polymerized powder in the bed region was 0.303 g / cm ³ . Moreover, to the reactor as the polymerization activity-reducing agent was added oxygen in a 4.2 mmol equivalent amount, as calculated in terms of the molecular weight of oxygen, per mole of triethylaluminum fed to the reactor of the first step of propylene polymerization. In the reactor, the mean residence time of the polymer particles was 2.9 hours, the gas concentration ratio (mole%) in the reactor for ethylene / (propylene + ethylene) 27 and for hydrogen / (hydrogen + propylene + ethylene) 0.59; the amount of discharged polymer particles 19.1 kg / h; the intrinsic viscosity of the copolymerized portion is 4.9 dl / g and the content of the copolymerized portion is 26 wt%.

Comparative Example 1

The Solution of a titanocene compound was the conduit of the circulating gas instead of the bed area supplied and the Polymerization was carried out while the Polymer holdup was adjusted so that the same content was obtained on the copolymerized part as in Example 1. In the reactor, the mean residence time of the polymer particles was 3.3 hours, the gas concentration ratio (mol%) in the reactor for ethylene / (propylene + ethylene) 27 and for hydrogen / (hydrogen + Propylene + ethylene) 0.91, the intrinsic viscosity of the copolymerized Partly 4.2 dl / g, the hydrogen concentration was high and the molecular weight of the copolymerized part was low.

Comparative Example 2

Without an entry of the solution of a titanocene compound the polymerization is carried out while the polymer holdup was adjusted so that the same content of the copolymerized Part was obtained as in Example 1. In the reactor was the Residence time of the polymer particles 3.9 h; the gas concentration ratio (Mol%) in the reactor for ethylene / (propylene + ethylene) 27 and for hydrogen / (hydrogen + propylene + ethylene) 1.5, the intrinsic viscosity 3.5 dl / g, the hydrogen concentration was high and the molecular weight of the copolymerized portion was low.

Example 2

A Prepolymerization catalyst component slurry carried out according to the method of Example 1 and three steps of propylene homopolymerizations were respectively in various reactors using the slurry formed for the production of polypropylene particles. In the following, each polymerization step will be explained.

First step of propylene polymerization (Liquid Phase)

Using a Bessel type reactor having an inner volume of 163 L and a fitted stirrer, homopolymerization of propylene was carried out. That is, propylene, hydrogen, triethylaluminum, cyclohexylethyldimethoxysilane, and the prepolymerization catalyst component slurry were continuously fed to the reactor. The reaction conditions were a polymerization temperature of 70 ° C, a stirring speed of 150 ^rpm-1, a quantity of liquid of the reactor of 44 l, a feed rate of propylene of 60 kg / h, a feed rate of hydrogen of 330 Nl / h, a feed rate of triethylaluminum of 41.2 mmol / hr, a feed rate of cyclohexylethyldimethoxysilane of 6.2 mmol / hr and a feed rate of prepolymerization catalyst component slurry (calculated with respect to the polymerization catalyst component) of 0.649 g / hr. In the reactor, the average residence time of the slurry was 0.29h and the amount of discharged polypropylene particles was 8.34kg / h. The intrinsic viscosity for this was 1.14 dl / g.

Second step of the propylene polymerization (Gas phase polymerization)

The polypropylene particles obtained by the above first propylene polymerization were continuously transferred to a fluidized bed reactor having an internal volume of 1.4 m ³ and a fitted stirrer, hydrogen was continuously supplied to this reactor, and homopolymerization of propylene was further carried out while discharging excess gas, to keep the pressure constant. The reaction conditions were a polymerization temperature of 70 ° C, a polymerization pressure of 1.6 MPa, a flow rate of the circulating gas of 100 m ³ / h, a feed rate of hydrogen of 1515 Nl / h, and a polymer particle holding amount in the wirepull of 30 kg. In the reactor, the average residence time of polymer particles was 1.7 hours, the gas concentration ratio (mol%) of hydrogen / (hydrogen + propylene) in the reactor was 6.9, the amount of discharged polymer particles was 17.2 kg / hr, and intrinsic viscosity thereof 1.12 dl / g.

Third step of propylene polymerization (Gas phase polymerization)

The polypropylene particles obtained by the above second propylene polymerization were continuously charged into another fluidized bed reactor having an internal volume of 1 m ³ and equipped with a gas diffusion plate and a stirrer was, convicted; Propylene and hydrogen were continuously supplied to this reactor, and homopolymerization of propylene was further conducted while the excess gas was discharged to keep the pressure constant. The reaction conditions were a polymerization temperature of 70 ° C, a polymerization pressure of 1.4 MPa, a flow rate of the circulating gas of 130 m ³ / h, a feed rate of propylene of 49.3 kg / hr and a polymer particle holding amount in the fluidized bed of 95 kg , Further, to the bed portion was added the above-mentioned solution of a titanocene compound in an amount corresponding to 7.28 mmol as calculated in terms of the molecular weight of titanocene per mole of triethylaluminum supplied to the reactor of the first step of propylene polymerization. The bulk density of the polymerized powder in the bed region was 0.320 g / cm ³ . In the reactor, the mean residence time of the polymer particles was 4.7 hours, the gas concentration ratio (mole%) in the reactor for hydrogen / (hydrogen + propylene) 0.033; the amount of the discharged polymer particles 20.3 kg / h and the intrinsic viscosity thereof 1.87 dl / g. That is, the intrinsic viscosity of the polymer particles prepared in the third step is 6.03 dl / g, and the propylene polymer produced in the third step of propylene polymerization has a higher molecular weight than that of the propylene polymer produced in the first step of the propylene polymerization, and in the second step of Polymer produced by propylene polymerization, with the result that a propylene polymer having a broad molecular weight distribution can be produced.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - JP 10-204123 A [0003]
• - JP 8-151408 A [0003]
• JP 57-63310A [0033]
• JP 58-83006A [0033]
• JP 61-78803A [0033]
• JP 7-216017A [0033]
• JP 10-212319 A [0033]
• JP 62-158704A [0033]
• JP 11-92518A [0033]
• - JP 5-155930 A [0033]
• JP 9-143217A [0033]
• - JP 2002-293817A [0033]
• JP 2003-171412 A [0033]
• - JP 8-511044 A [0033]
• - JP 2001-31720 A [0033]
• - JP 2008-27945 [0088]

Cited non-patent literature

• "Polymer Solution, Polymer Experimental Study 11" (published by Kyoritsu Shuppan Co., Ltd., 1982), page 491 [0084]

Claims (2)

Process for the preparation of an olefin polymer, which includes the following stages: Use of a gas phase reaction vessel, Polymerization of an olefin using a catalyst for olefin polymerization in the presence of hydrogen and encore a hydrogenation catalyst to a bed region in the gas phase reaction vessel. Process for the preparation of an olefin polymer according to Claim 1, wherein the hydrogenation catalyst is a titanocene compound contains.